Particularly during conditions of rain or snow, heavy vehicles such as trucks, tractor trailers and buses generate clouds of spray either beside or behind them, as a result of the action of their wheels on the roadway surface, as they travel over such surface. As well, other road surface materials such as mud, pebbles, salt and dust may be propelled upwardly in a spray to either side or behind such vehicle. Such sprays are dispersed into adjacent traffic lanes making it dangerous or impossible for that vehicle to be passed by another, or making it dangerous or hazardous to follow behind such vehicle or for oncoming traffic to go by that vehicle.
Such problems have been previously recognized and many solutions proposed. For example, U.S. Pat. No. 4,192,522 of Morgan issued Mar. 11, 1980 describes a splash and spray control shield for the wheels of large vehicles consisting of a shield which covers the upper parts of a wheel, and has, at its forward end, a funnel-like air scoop which sits over the upper front half of the wheels and which defines an enlarged front opening and a constricted rear opening through which the flow of air from in front of the scoop is forcefully directed rearwardly along the top wall of the shield. A resilient shield extension is fastened to the rear section of the shield to downwardly direct the spray to the road surface. This construction of shield generates additional wind resistance on such a device; the faster the vehicle moves, the greater the wind resistance generated by the vehicle. The use of the scoop device to force air over the wheels, as well as the resilient shield extension at the rear of the shield generates increased pressure and turbulence within the device which can carry spray to the sides of the vehicle.
In my U.S. Pat. No. 4,660,846 issued Apr. 28, 1987, I described and illustrated a louvered spray shield to be placed behind the wheels of large vehicles, the louvers of which shield directed air through the louvers and downwardly towards the roadway surface, thereby significantly reducing the spray generated by the wheels of such a vehicle.
Other patents of general background interest are Wenham, et al U.S. Pat. No. 2,619,363 issued Nov. 25, 1952; Eaves U.S. Pat. No. 2,940,773 issued Jun. 14, 1960; Barry, et al U.S. Pat. No. 3,088,751 issued May 7, 1963; Salisbury U.S. Pat. No. 3,350,114 issued Oct. 31, 1967; Jones U.S. Pat. No. 3,279,818 issued Oct. 18, 1966; Iwanicki U.S. Pat. No. 4,334,694 issued Jun. 15, 1982; Brandon, et al U.S. Pat. No. 4,325,563 issued Apr. 20, 1982; and Grote, et al Canadian Patent No. 955,290 issued Sept. 24, 1974, all of these patents describing and illustrating various constructions of vehicle splash guards which have been previously proposed.